1. Field of the Invention
This invention relates to a storage and dispensing container for compositions that are made of two or more components. This invention also relates to a dispensing assembly that includes a container and an applicator for dispensing a composition from the container.
2. Description of the Related Art
A variety of compositions are sold to consumers or other end users in packages or containers that keep certain components of the composition isolated from each other until the composition is needed for use. For example, epoxy-based adhesives are widely available in packages that include two compartments or containers that keep components of the adhesive initially separate. The components are not mixed together until the adhesive is needed, because once the components come into contact with each other a chemical reaction is undertaken that eventually turns the mixed composition into a hardened mass.
Containers for multiple component compositions are also widely used in the field of medicine and dentistry, including orthodontia. For example, many adhesives and cements used in dentistry are made of two liquid components that are initially kept apart from each other. Examples of two-component dental compositions include RelyX ARC dental cement and F2000 primer/adhesive, both from 3M Company.
In the past, some storage and dispensing containers for multiple-component compositions were relatively large and contained a sufficient quantity of the components for multiple applications at different times. Examples of such bulk containers include cans and jars. In use, a portion of the total quantity of each component would be measured and withdrawn from each container and transferred to a mixing location, such as a mixing well or mixing pad. Such bulk containers are in widespread use in certain applications because the costs of packaging the components are relatively low.
However, the practice of supplying multiple-component compositions in two initially separate bulk containers is not entirely satisfactory. If, for example, the user does not withdraw components from the bulk containers in the proper ratio, the characteristics of the resulting composition may be significantly impaired. Additionally, the portions of the components that remain in the container may be adversely affected over a period of time by exposure to the atmosphere once the container is opened. Furthermore, the user is often compelled to dispose of the mixing well, pad or other mixing structure after a single use, or undergo an effort to clean the same in preparation for a subsequent use.
In recent years, there has been increased interest in xe2x80x9csingle usexe2x80x9d or xe2x80x9csingle dosexe2x80x9d containers for compositions made of two components that are initially kept apart from each other. Such containers typically avoid the need to measure out separate quantities of each component before mixing and help assure that the components, when mixed, are present in the desired ratio. Additionally, if the components are mixed together within the container, the need for a mixing well, mixing pad or other type of mixing structure is avoided.
Examples of containers that are especially suitable for isolated storage of components for multiple component compositions are described, for example, in U.S. Pat. Nos. 5,735,437 and 5,743,736.
The present invention is related to an improved storage, mixing and dispensing container for compositions that are made of two or more components. The container is especially suitable for single-use applications, such as those found in the field of dentistry. In certain aspects, the container of the invention includes a surface having protrusions for facilitating mixing of the components. Other aspects of the invention are directed toward a container with an improved applicator, a container with an improved outer configuration, an articulated container and related methods.
In more detail, the present invention is directed in one embodiment toward a storage and dispensing container that comprises a housing having wall sections defining a chamber with an opening. A first sheet extends across the chamber and is connected to the housing, and a second sheet extends across at least a portion of the first sheet and is connected to the housing. A compartment is located between the first sheet and the second sheet. A first component is received in the chamber, and a second component is received in the compartment. The first sheet and the second sheet are rupturable in order to enable the first component to mix together. At least a portion of the wall sections include a plurality of protrusions for facilitating mixing of the components.
The present invention is also directed in another embodiment toward a storage and dispensing container. In this embodiment, the container includes a housing having side wall sections presenting an internal wall surface and an external surface opposite the internal surface. The housing also has a chamber surrounded by the internal wall surface. The chamber has a central longitudinal axis and an opening. The container also includes a first sheet that extends across the chamber and is connected to the housing, and a second sheet that extends across at least a portion of the first sheet and is connected to the housing. A compartment is located between the first sheet and the second sheet. A first component is received in the chamber, and a second component is received in the compartment. The first sheet and the second sheet are rupturable in order to enable the first component and the second component to mix together. The longitudinal axis of the chamber is inclined upwardly toward the opening when the external wall surface of the housing is lying in a horizontal plane.
The present invention is also directed to a storage and dispensing assembly. The assembly comprises a container including a housing having an internal wall surface with an opening. The container also includes at least one component of a composition received in the chamber and at least one sheet extending across the chamber and connected to the housing. Each sheet is rupturable in order to access each component. The assembly also comprises an applicator having an elongated shaft and an outer tip. The applicator also includes structure spaced from the tip and extending outwardly from the shaft in order to facilitate rupturing of each sheet as the tip is moved into the chamber.
Another embodiment of the present invention is directed toward a method of dispensing a composition made from two or more components. The method includes the act of providing a container having an elongated chamber with a first component and a compartment with a second component, wherein the first component and the second component are initially separated from each other. The method also includes the act of fracturing a rupturable sheet located between the chamber and the compartment with an applicator in order to enable the first component and the second component to contact each other. The method further includes the act of moving a tip of the applicator along a longitudinal axis of the chamber in order to mix the first component and the second component. The act of moving the tip of the applicator along the longitudinal axis of the chamber includes the act of moving the first component and the second component adjacent a surface having a plurality of protrusions in order to facilitate mixing of the components.
The present invention is also directed in another embodiment toward a method of dispensing a composition from a container. In this embodiment, the method includes the act of providing a container having a chamber with an opening and a rupturable sheet extending across the chamber. The method also includes the act of providing an applicator having an elongated shaft, a tip connected to one end of the shaft and protruding structure connected to the shaft at a location remote from the tip. The method further includes the act of pressing the tip of the applicator against the sheet in order to rupture the sheet and create an aperture. The method additionally includes the act of moving the tip of the applicator through the aperture and into the chamber in order to access a composition in the chamber. The act of moving the tip into the chamber includes the act of urging the protruding structure of the applicator against the sheet in order to enlarge the aperture that was created by the tip.
These and other aspects of the invention are described in more detail in the paragraphs that follow and are illustrated in the accompanying drawings.